Left 4 Dead 2

The dead shall inherit the Earth. Again, actually, if Valve have anything to say about it. Despite some valiant former attempts at zombie genocide, there are still plenty of the walking dead to shoot in America's southern states. In a perfect world I'd just be able to hide in a closet until the bother dies down, but that apparently wouldn't make for a very good first-person shooter. This is why I'm not the one in charge of Left 4 Dead 2.

After some recent hands-on time with both the PC and 360 versions I can easily say, without wanting to engage in a bout of format snobbery, that the 360 version is not without fault. It's locked to 30fps, for a start - a PC built five years ago can comfortably push out double that. But the bigger elephant in the room is still the controls: precisely thinning down the voluminous amounts of pale-skinned on-screen monstrosities with the Xbox controller occasionally seems to be too much to ask of Microsoft's twin sticks.

Of course, it's relatively easy to adjust if you're not keen on the idea of playing games on the PC. But that didn't stop the team of random players I was matched up with at a recent EA event getting embroiled within endlessly repetitive friendly-fire incidents, with Valve's Chet Falisek looking on from the sidelines - disappointment clearly visible in his eyes. Though in this instance it was a case of a bad workman blaming his tools: despite being flashed up with enticing melee weapons - Guitar! Nightstick! A flippin' chainsaw! - Left 4 Dead's fundamental tenets of sticking together and working closely as a team are more valid than ever. It ultimately comes as no surprise that, when a whole team is trying to clang zombies to death with the business end of a frying pan, the AI director can effortlessly swoop in and clean up.

The aforementioned AI director remains the silent star of the show. A good team - be they a group of human survivors or undead infected over in the game's versus mode - succeeds by respecting the ebbs and flows of the AI's desires. It knows when to back off, how to lull you into a false sense of security and from which areas to funnel masses of zombies through to cause you the most grief. It's a sneaky one, and Valve clearly hold its influence over the game in high regard; they've upped the ante in the sequel by giving it a variety of new tricks to tinker with, most notably the new special infected and the inclusion of 'gauntlet' areas in each campaign.

A good example of the latter can be seen in the section at the end of the recently released demo (which takes place during The Parish campaign - one of five included in the game), where you're running through a fenced-off quarantine area, fleeing from the infected behind you whilst shooting a path through the ones ahead. I also experienced a similar section in Dark Carnival (tagline: "you must be this tall... TO DIE") when the survivors had to navigate across a narrow, twisting and blatantly perilous rollercoaster track to reach the end of the level. Nail biting stuff - especially when you see a Smoker looming on the horizon. These sections add a delightful change of pace to the flow of the campaigns, when previously the more daring crescendos were all about staying relatively still in one area and fending off waves of gnarly attackers.

Another major difference this time around is a newfound versatility in aesthetic design, which should help revitalise the spirits of anyone getting weary of guiding Louis, Zoey, Francis and Bill to safety. The Parish, for instance, features plenty of vibrant, daytime yellows, whereas Dark Carnival presents a variety of gaudy purples. Neither is set at night, and both look like nothing from the first game. One of the problems with the original Left 4 Dead is that certain areas of the game had a tendency to be homogenous with others: hardly a major criticism when considering that each campaign had more examples of its own distinct design, but an area in which the sequel has tried to do away with completely. And it looks like they have.

Getting all the schlock B-Movie stereotypes out of the way in the original has evidently given Valve room to think more creatively, with an overall narrative taking the four new survivors through a violent trip through America's Deep South. Creep off the beaten path and take in some of the scenery and, from what I've seen, it's all shameful relics from humanity's less desirable qualities: mass consumption, needless excess and tacky garden furniture. It's a different tack from the original's fascination with bringing down humanity's achievements with hospitals, airports et al.

And what of the new survivors, whose announcement was met with vibrant hostility from many fans? They're all fantastic, actually. White-suited conman Nick provides the abject cynicism, burly Coach tries to foster morale whilst lamenting his middle-aged spread, stereotypical hick Ellis stumbles around with his goofy accent and Rochelle kicks zombie bottom (in a Depeche Mode t-shirt!) and is flirtatious. And Chicago Ted, who no zombie is safe from, will possibly make a return.

Then there's the new special infected, which take the forms of the Jockey, which can leap onto a survivor and commandeer them into peril, the Charger, who barrels through a group of survivors and grabs one to clobber, and the Spitter, who can attack round corners by hocking corrosive globs of acid that seep across the floor.

The new infected slot straight into the game, and after a couple of rounds feel as familiar as the original Smoker, Hunter and Boomer trio - who have all successfully managed to emigrate to the warmer climate. The additions to the roster all serve a very distinct purpose; the Spitter is able to break up campers, the Charger forces groups who walk around in tight clusters to rethink their strategy and the Jockey's ability to guide players means it's now easier to force hapless survivors into orchestrated traps. Couple it with the fact the Witch can now walk around and the Tank will focus on attacking more than one survivor at a time and players familiar with the original will clearly need to adjust their tactics - a very good thing.

There are also regular appearances from the convolutedly-titled uncommon common infected. Each campaign has its own particular nasty, which has an intended side-effect of making each campaign more distinctive, and they all take the form of regular baddies with a slight twist, such as squeaky, noisy clowns in Dark Carnival, who attract other infected, and the riot police in The Parish, who can only be shot from behind. They're a subtle addition, but add just enough to the tried-and-tested formula to keep you perpetually alert.

It might all seem like a lot to take in, especially when remembering how the original Left 4 Dead was an exercise in the fundamentals: whilst its developmental-sibling Team Fortress 2 was adding in all sorts of whizzy gadgets and fancy doohickies, Left 4 Dead presented an entirely Spartan set of weapons and items. At first the sequel seems to have thrown off the delicate mix, adding in a middle-tier of weapons and plenty more gadgets alongside with the ever-satisfying melee tools. There's even a defibrillator, which can forego the closet respawn and immediately resurrect downed players at the cost of being able to carry a health pack.

But all this fancy new swag goes even further to emphasise the game's potent risk-and-reward system. Melee weapons take your pistol slot and demand you tussle with the infected head-on, which proves to be an incredibly dangerous action on Advanced (the best mode) and Expert (a bit too hard) difficulties. The new weapons, such as a silenced sub-machine gun and AK47, add a dose of much-needed variety to levels, and the new items give you abilities you'll definitely need to take on the faster, stronger AI hordes. What originally seemed superfluous quickly becomes iconic, and you're left perplexed as to how you ever played the game without the occasional jar of Boomer Bile.

Left 4 Dead 2 is definitely more than more of the same: Valve are clearly striving to enhance the original whilst staying true to its much-loved core gameplay. And, unless the other three campaigns turn out to be complete rubbish, it's already clear they've succeeded. If there's a multiplayer game this holiday season with enough potency to drag players away from Modern Warfare 2, this is it.